1. Field of the Invention
The invention relates to a process for the manufacture of a catalyst containing metal oxide for the reduction of nitrogen oxides in exhaust gases, specifically for the reduction of nitrogen oxides in exhaust gases by catalytic reduction by means of ammonia.
2. Description of the Prior Art
The prior art includes numerous processes for the removal of nitrogen oxides from exhaust gases. Among such processes, selective catalytic reduction by means of ammonia has proven particularly effective. Various catalysts can be used, comprising primarily metal oxides. Other active substances can be added to these metal oxides. Several disadvantages of catalysts of the prior art are that they are not resistant to abrasion or to impacts. They do not exhibit a compression-proof consistency, and they are expensive to produce. The last-named disadvantage results primarily from the fact that the production of the active substances requires several complicated steps involving the treatment of the primary materials, and from the fact that special techniques must be used to obtain the desired shapes. Examples of prior art are German Pat. No. DE-PS 25 12 410 which corresponds to U.S. Pat. No. 4,087,250, entitled "Apparatus for Removing Nitric Oxides from Processing Exhaust Gases" and U.S. Pat. No. 4,081,511, entitled "Process for Removing Nitric Oxides from Processing Exhaust Gases" and German Laid Open Patent Application No. DE-OS 25 12 409, all of which are incorporated by reference as if fully set forth herein.